1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
|
#ifndef __LINUX_RTNETLINK_H
#define __LINUX_RTNETLINK_H
#include <linux/types.h>
#include <linux/netlink.h>
#include <linux/if_link.h>
#include <linux/if_addr.h>
#include <linux/neighbour.h>
/****
* Routing/neighbour discovery messages.
****/
/* Types of messages */
enum {
RTM_BASE = 16,
#define RTM_BASE RTM_BASE
RTM_NEWLINK = 16,
#define RTM_NEWLINK RTM_NEWLINK
RTM_DELLINK,
#define RTM_DELLINK RTM_DELLINK
RTM_GETLINK,
#define RTM_GETLINK RTM_GETLINK
RTM_SETLINK,
#define RTM_SETLINK RTM_SETLINK
RTM_NEWADDR = 20,
#define RTM_NEWADDR RTM_NEWADDR
RTM_DELADDR,
#define RTM_DELADDR RTM_DELADDR
RTM_GETADDR,
#define RTM_GETADDR RTM_GETADDR
RTM_NEWROUTE = 24,
#define RTM_NEWROUTE RTM_NEWROUTE
RTM_DELROUTE,
#define RTM_DELROUTE RTM_DELROUTE
RTM_GETROUTE,
#define RTM_GETROUTE RTM_GETROUTE
RTM_NEWNEIGH = 28,
#define RTM_NEWNEIGH RTM_NEWNEIGH
RTM_DELNEIGH,
#define RTM_DELNEIGH RTM_DELNEIGH
RTM_GETNEIGH,
#define RTM_GETNEIGH RTM_GETNEIGH
RTM_NEWRULE = 32,
#define RTM_NEWRULE RTM_NEWRULE
RTM_DELRULE,
#define RTM_DELRULE RTM_DELRULE
RTM_GETRULE,
#define RTM_GETRULE RTM_GETRULE
RTM_NEWQDISC = 36,
#define RTM_NEWQDISC RTM_NEWQDISC
RTM_DELQDISC,
#define RTM_DELQDISC RTM_DELQDISC
RTM_GETQDISC,
#define RTM_GETQDISC RTM_GETQDISC
RTM_NEWTCLASS = 40,
#define RTM_NEWTCLASS RTM_NEWTCLASS
RTM_DELTCLASS,
#define RTM_DELTCLASS RTM_DELTCLASS
RTM_GETTCLASS,
#define RTM_GETTCLASS RTM_GETTCLASS
RTM_NEWTFILTER = 44,
#define RTM_NEWTFILTER RTM_NEWTFILTER
RTM_DELTFILTER,
#define RTM_DELTFILTER RTM_DELTFILTER
RTM_GETTFILTER,
#define RTM_GETTFILTER RTM_GETTFILTER
RTM_NEWACTION = 48,
#define RTM_NEWACTION RTM_NEWACTION
RTM_DELACTION,
#define RTM_DELACTION RTM_DELACTION
RTM_GETACTION,
#define RTM_GETACTION RTM_GETACTION
RTM_NEWPREFIX = 52,
#define RTM_NEWPREFIX RTM_NEWPREFIX
RTM_GETMULTICAST = 58,
#define RTM_GETMULTICAST RTM_GETMULTICAST
RTM_GETANYCAST = 62,
#define RTM_GETANYCAST RTM_GETANYCAST
RTM_NEWNEIGHTBL = 64,
#define RTM_NEWNEIGHTBL RTM_NEWNEIGHTBL
RTM_GETNEIGHTBL = 66,
#define RTM_GETNEIGHTBL RTM_GETNEIGHTBL
RTM_SETNEIGHTBL,
#define RTM_SETNEIGHTBL RTM_SETNEIGHTBL
RTM_NEWNDUSEROPT = 68,
#define RTM_NEWNDUSEROPT RTM_NEWNDUSEROPT
RTM_NEWADDRLABEL = 72,
#define RTM_NEWADDRLABEL RTM_NEWADDRLABEL
RTM_DELADDRLABEL,
#define RTM_DELADDRLABEL RTM_DELADDRLABEL
RTM_GETADDRLABEL,
#define RTM_GETADDRLABEL RTM_GETADDRLABEL
RTM_GETDCB = 78,
#define RTM_GETDCB RTM_GETDCB
RTM_SETDCB,
#define RTM_SETDCB RTM_SETDCB
__RTM_MAX,
#define RTM_MAX (((__RTM_MAX + 3) & ~3) - 1)
};
#define RTM_NR_MSGTYPES (RTM_MAX + 1 - RTM_BASE)
#define RTM_NR_FAMILIES (RTM_NR_MSGTYPES >> 2)
#define RTM_FAM(cmd) (((cmd) - RTM_BASE) >> 2)
/*
Generic structure for encapsulation of optional route information.
It is reminiscent of sockaddr, but with sa_family replaced
with attribute type.
*/
struct rtattr {
unsigned short rta_len;
unsigned short rta_type;
};
/* Macros to handle rtattributes */
#define RTA_ALIGNTO 4
#define RTA_ALIGN(len) ( ((len)+RTA_ALIGNTO-1) & ~(RTA_ALIGNTO-1) )
#define RTA_OK(rta,len) ((len) >= (int)sizeof(struct rtattr) && \
(rta)->rta_len >= sizeof(struct rtattr) && \
(rta)->rta_len <= (len))
#define RTA_NEXT(rta,attrlen) ((attrlen) -= RTA_ALIGN((rta)->rta_len), \
(struct rtattr*)(((char*)(rta)) + RTA_ALIGN((rta)->rta_len)))
#define RTA_LENGTH(len) (RTA_ALIGN(sizeof(struct rtattr)) + (len))
#define RTA_SPACE(len) RTA_ALIGN(RTA_LENGTH(len))
#define RTA_DATA(rta) ((void*)(((char*)(rta)) + RTA_LENGTH(0)))
#define RTA_PAYLOAD(rta) ((int)((rta)->rta_len) - RTA_LENGTH(0))
/******************************************************************************
* Definitions used in routing table administration.
****/
struct rtmsg {
unsigned char rtm_family;
unsigned char rtm_dst_len;
unsigned char rtm_src_len;
unsigned char rtm_tos;
unsigned char rtm_table; /* Routing table id */
unsigned char rtm_protocol; /* Routing protocol; see below */
unsigned char rtm_scope; /* See below */
unsigned char rtm_type; /* See below */
unsigned rtm_flags;
};
/* rtm_type */
enum {
RTN_UNSPEC,
RTN_UNICAST, /* Gateway or direct route */
RTN_LOCAL, /* Accept locally */
RTN_BROADCAST, /* Accept locally as broadcast,
send as broadcast */
RTN_ANYCAST, /* Accept locally as broadcast,
but send as unicast */
RTN_MULTICAST, /* Multicast route */
RTN_BLACKHOLE, /* Drop */
RTN_UNREACHABLE, /* Destination is unreachable */
RTN_PROHIBIT, /* Administratively prohibited */
RTN_THROW, /* Not in this table */
RTN_NAT, /* Translate this address */
RTN_XRESOLVE, /* Use external resolver */
__RTN_MAX
};
#define RTN_MAX (__RTN_MAX - 1)
/* rtm_protocol */
#define RTPROT_UNSPEC 0
#define RTPROT_REDIRECT 1 /* Route installed by ICMP redirects;
not used by current IPv4 */
#define RTPROT_KERNEL 2 /* Route installed by kernel */
#define RTPROT_BOOT 3 /* Route installed during boot */
#define RTPROT_STATIC 4 /* Route installed by administrator */
/* Values of protocol >= RTPROT_STATIC are not interpreted by kernel;
they are just passed from user and back as is.
It will be used by hypothetical multiple routing daemons.
Note that protocol values should be standardized in order to
avoid conflicts.
*/
#define RTPROT_GATED 8 /* Apparently, GateD */
#define RTPROT_RA 9 /* RDISC/ND router advertisements */
#define RTPROT_MRT 10 /* Merit MRT */
#define RTPROT_ZEBRA 11 /* Zebra */
#define RTPROT_BIRD 12 /* BIRD */
#define RTPROT_DNROUTED 13 /* DECnet routing daemon */
#define RTPROT_XORP 14 /* XORP */
#define RTPROT_NTK 15 /* Netsukuku */
#define RTPROT_DHCP 16 /* DHCP client */
/* rtm_scope
Really it is not scope, but sort of distance to the destination.
NOWHERE are reserved for not existing destinations, HOST is our
local addresses, LINK are destinations, located on directly attached
link and UNIVERSE is everywhere in the Universe.
Intermediate values are also possible f.e. interior routes
could be assigned a value between UNIVERSE and LINK.
*/
enum rt_scope_t {
RT_SCOPE_UNIVERSE=0,
/* User defined values */
RT_SCOPE_SITE=200,
RT_SCOPE_LINK=253,
RT_SCOPE_HOST=254,
RT_SCOPE_NOWHERE=255
};
/* rtm_flags */
#define RTM_F_NOTIFY 0x100 /* Notify user of route change */
#define RTM_F_CLONED 0x200 /* This route is cloned */
#define RTM_F_EQUALIZE 0x400 /* Multipath equalizer: NI */
#define RTM_F_PREFIX 0x800 /* Prefix addresses */
/* Reserved table identifiers */
enum rt_class_t {
RT_TABLE_UNSPEC=0,
/* User defined values */
RT_TABLE_COMPAT=252,
RT_TABLE_DEFAULT=253,
RT_TABLE_MAIN=254,
RT_TABLE_LOCAL=255,
RT_TABLE_MAX=0xFFFFFFFF
};
/* Routing message attributes */
enum rtattr_type_t {
RTA_UNSPEC,
RTA_DST,
RTA_SRC,
RTA_IIF,
RTA_OIF,
RTA_GATEWAY,
RTA_PRIORITY,
RTA_PREFSRC,
RTA_METRICS,
RTA_MULTIPATH,
RTA_PROTOINFO, /* no longer used */
RTA_FLOW,
RTA_CACHEINFO,
RTA_SESSION, /* no longer used */
RTA_MP_ALGO, /* no longer used */
RTA_TABLE,
__RTA_MAX
};
#define RTA_MAX (__RTA_MAX - 1)
#define RTM_RTA(r) ((struct rtattr*)(((char*)(r)) + NLMSG_ALIGN(sizeof(struct rtmsg))))
#define RTM_PAYLOAD(n) NLMSG_PAYLOAD(n,sizeof(struct rtmsg))
/* RTM_MULTIPATH --- array of struct rtnexthop.
*
* "struct rtnexthop" describes all necessary nexthop information,
* i.e. parameters of path to a destination via this nexthop.
*
* At the moment it is impossible to set different prefsrc, mtu, window
* and rtt for different paths from multipath.
*/
struct rtnexthop {
unsigned short rtnh_len;
unsigned char rtnh_flags;
unsigned char rtnh_hops;
int rtnh_ifindex;
};
/* rtnh_flags */
#define RTNH_F_DEAD 1 /* Nexthop is dead (used by multipath) */
#define RTNH_F_PERVASIVE 2 /* Do recursive gateway lookup */
#define RTNH_F_ONLINK 4 /* Gateway is forced on link */
/* Macros to handle hexthops */
#define RTNH_ALIGNTO 4
#define RTNH_ALIGN(len) ( ((len)+RTNH_ALIGNTO-1) & ~(RTNH_ALIGNTO-1) )
#define RTNH_OK(rtnh,len) ((rtnh)->rtnh_len >= sizeof(struct rtnexthop) && \
((int)(rtnh)->rtnh_len) <= (len))
#define RTNH_NEXT(rtnh) ((struct rtnexthop*)(((char*)(rtnh)) + RTNH_ALIGN((rtnh)->rtnh_len)))
#define RTNH_LENGTH(len) (RTNH_ALIGN(sizeof(struct rtnexthop)) + (len))
#define RTNH_SPACE(len) RTNH_ALIGN(RTNH_LENGTH(len))
#define RTNH_DATA(rtnh) ((struct rtattr*)(((char*)(rtnh)) + RTNH_LENGTH(0)))
/* RTM_CACHEINFO */
struct rta_cacheinfo {
__u32 rta_clntref;
__u32 rta_lastuse;
__s32 rta_expires;
__u32 rta_error;
__u32 rta_used;
#define RTNETLINK_HAVE_PEERINFO 1
__u32 rta_id;
__u32 rta_ts;
__u32 rta_tsage;
};
/* RTM_METRICS --- array of struct rtattr with types of RTAX_* */
enum {
RTAX_UNSPEC,
#define RTAX_UNSPEC RTAX_UNSPEC
RTAX_LOCK,
#define RTAX_LOCK RTAX_LOCK
RTAX_MTU,
#define RTAX_MTU RTAX_MTU
RTAX_WINDOW,
#define RTAX_WINDOW RTAX_WINDOW
RTAX_RTT,
#define RTAX_RTT RTAX_RTT
RTAX_RTTVAR,
#define RTAX_RTTVAR RTAX_RTTVAR
RTAX_SSTHRESH,
#define RTAX_SSTHRESH RTAX_SSTHRESH
RTAX_CWND,
#define RTAX_CWND RTAX_CWND
RTAX_ADVMSS,
#define RTAX_ADVMSS RTAX_ADVMSS
RTAX_REORDERING,
#define RTAX_REORDERING RTAX_REORDERING
RTAX_HOPLIMIT,
#define RTAX_HOPLIMIT RTAX_HOPLIMIT
RTAX_INITCWND,
#define RTAX_INITCWND RTAX_INITCWND
RTAX_FEATURES,
#define RTAX_FEATURES RTAX_FEATURES
RTAX_RTO_MIN,
#define RTAX_RTO_MIN RTAX_RTO_MIN
__RTAX_MAX
};
#define RTAX_MAX (__RTAX_MAX - 1)
#define RTAX_FEATURE_ECN 0x00000001
#define RTAX_FEATURE_NO_SACK 0x00000002
#define RTAX_FEATURE_NO_TSTAMP 0x00000004
#define RTAX_FEATURE_ALLFRAG 0x00000008
#define RTAX_FEATURE_NO_WSCALE 0x00000010
#define RTAX_FEATURE_NO_DSACK 0x00000020
struct rta_session {
__u8 proto;
__u8 pad1;
__u16 pad2;
union {
struct {
__u16 sport;
__u16 dport;
} ports;
struct {
__u8 type;
__u8 code;
__u16 ident;
} icmpt;
__u32 spi;
} u;
};
/****
* General form of address family dependent message.
****/
struct rtgenmsg {
unsigned char
|